Which from following cations develops lowest value of spin only magnetic moment?

Step-by-step solution

Spin-only magnetic moment is given by = n(n + 2) , BM , where n is the number of unpaired electrons in the cation. V³⁺ has configuration [ Ar ] , 3d^2 with n = 2 , 2.83 , BM . Cr ³⁺ has [ Ar ] , 3d^3 , n = 3 , 3.87 , BM . Mn ²⁺ has [ Ar ] , 3d^5 , n = 5 , 5.92 , BM . Fe ²⁺ has [ Ar ] , 3d^6 , n = 4 , 4.90 , BM . The minimum magnetic moment is approximately 2.83 , BM , corresponding to V³⁺ .